GiddyUp Txt App-Vites for Socializing Quickies

Planning social event and getting your friends all together in the same place at the same time can be really difficult. What is the best way to round them up new(or giddyup) on short notice? (video follows)

Evite, works well for email in advance of the party. Sometimes people check Facebook timelines in time. Some people prefer phone calls, FourSquare check-ins, text messages or maybe you could as the Brits say "knock them up" by knocking on their doors.

Now there is an Android and iPhone app for that. GiddyUp claims the app makes social event planning easy and efficient. The app requires a smartphone with Internet and SMS to participate in group planning, no sign?up required.